Hypertension = High arterial blood pressure. It is
measured in milimeters of mercury (mmHg) using a
sphygmomanometer.
Symptoms of Hypertension
It occasionally causes headache, but hypertension per se is
asymptomatic. The causes (listed below) may have other
symptoms.
Causes of Hypertension
95% of clinical hypertension is "primary" or "essential",
meaning idiopathic. The causes of secondary hypertension are
three quarters renal, e.g. polycystic kidney disease,
acute glormerulonephritis, pyelonephritis,
systemic sclerosis, or renovascular ie atheromatous
plaques in the renal arteries.
Endocrine causes of secondary
hypertension include Conns disease, Cushings disease,
phaeochromocytoma and hyperparathyroidism.
Drugs that increase blood pressure include the Combined Oral Contraceptive Pill, Monoamine Oxidase
Inhibitors and Steroids.
Other causes of hypertension include pregnancy and
coarctation of the aorta.
Why Treat?
The incidence of coronary artery disease and stroke is
closely related to average blood pressure.1 Anti-hypertensive
therapy reduces the incidence of stroke and, to a lesser extent,
coronary artery disease.
When to Treat
Any cut off point to define hypertension is arbitrary as the
higher the blood pressure, the higher the risks. Even a person with
an average blood pressure would reduce their risk by
anti-hypertensive treatment. In an attempt to balance the risks
and costs of treatment with the benefits, A cut off point for
treatment of > 140 mmHg systolic or > 90 mmHg diastolic (see
measuring blood pressure) is used in practice. Although
hypertension seems to increase naturally with age, treating a
given blood pressure has more benefit in an elderly person.
Other risk Factors for cardiovascular disease, when present,
make it more important to treat hypertension in any particular
individual. For example, males, blacks, smokers,
diabetics, those with poor diet, a relevent family
history, high cholesterol or pre-existing vascular disease
benefit more from treatment to lower their blood pressure.
Treatments of Hypertension - Modification of risk
factors
lifestyle modifications can reduce blood pressure. For example,
reducing the sodium content in the diet, reducing alcohol use,
increasing vegetables in the diet, increasing exercise and
reducing obesity all help. Stress should also be addressed,
particularly in those with personality type
'A'.
Pharmacological Treatment of
Hypertension
After these, options such as clonidine, and methyldopa can
be considerd. Diabetic patients should be started immediately on
ACE i. Target
blood pressures for diabetic patients are also lower.
1. Chobanian AV, Bakris GL, Black HR, et al. Seventh report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure. Hypertension 2003;42(6):1206-52